Counterweights are used to balance vehicles such as riding lawnmowers. Counterweights are used when a riding lawnmower or tractor carries an attachment that causes the vehicle to become unbalanced. A counterweight apparatus works best for an operator if it is versatile and easy to use. A counterweight apparatus is versatile if it is possible to mount one, some or all of a set of generally identical counterweights. It is preferable that the individual counterweights be generally identical, heavy enough to provide a significant counterweight for the vehicle and relatively easy to install and remove.